Shoe stiffener



Feb. 2, 1932. Y 4 P.' LQVELL 1,843,687.V

SHOE STIFEENER Original Filed May A2O, 1929 4.

Patented Feb. 2, 1932 UNITED STATES' PATENT OFFICE i STANLEY T.. LovELL, OF NEWTON, uAssAoHUsETTs, AssIGNoa To ABDEN Box TOE GOMPANY, OF WATERTOWN, MASSACHUSETTS, A CORPORATION or uAssAoHUsETTs Original application filed Hay 20, 1929, Serial No. 384,413. Divided and this 1930. Serial No. 456,045.

This invention relates to stiHenerS, more particularly for the toe portions of shoes and of that type wherein the stiifeners reach the shoemaker in softened condition ready for incorporation directly into shoes and for lasting without preliminary conditioning treatiment. The stiffening agentfor imparting stiffness to stiffeners of this type is one which is softened by a solvent, usually non-aqueous, and which evaporates after the stifl'ener is exposed to the air, and in order that the stiffeners may be in proper condition for the shoe l' manufacturer, they are packed in hermetically sealed containers which revent evaporation of the solvent until it 1s desired to use them at the shoe factory when the container is o ned.

i ore specifically the present invention relates to a stiil'ener, more especially adapted foruse in the manufacture of turn shoes, and wherein an external face of the stiifener is in tacky condition when it is assembled in the shoe so that it may adhere firmly to the adjacent shoe' part or parts so as to permit turning of the shoe after lasting without displacing the stiifener. This application is a division of my application Serial No. 364,413, led May 20, 1929, for Shoe stitfeners and method and means for packaging and handling the same.

In accordance with this invention the stiffener is preferably made with one or more lay.V ers of fabric, preferably two layers, each of which is coated on one or both faces with a suitable stifi'ening agent softenable with a volatile solvent. The stiffeners after treatment with the solvent are then stacked between vprotective separator sheets to which they do not strongly adhere and the separator sheets are so formed as to facilitate the placing of the stiifeners in assembled relation in shoes.

While this invention is not limited thereto, a stifi'ening agent which has been found very satisfactory is an ester of cellulose. By proper choice of the volatile solvent used, it is possible to control the time of hardening of the stiffener after it has been removed from its container, this time of hardening being predetermined in accordance with the application led Iay 27,

character of the shoes being made and with particular relation to the particular problems and equipment of the individual shoe factory.

For a more complete understanding of this invention, reference may be had to the accompanying drawings in which Figure 1 lis a plan of a separator sheet prepared to receive a treated stiifener prior to ackaging.

igure 2 is a plan showing a treated stiffener in place bn the separator sheet.

Figure 3 shows in perspective a stack of stifene-rs and interposed separator sheets showin in dotted lines the manner in whichl the sti eners can be removed successively from the stack for use. l

Figures 4 and 5 are sections through a stiifener and separator sheet showing successive stages in the removal of the stiffener from the sheet.

Referring to the drawings,'1 indicates a i shoe stifener, such for example as a box toe, which is composed of one or more plies of fabric as 2 and 3 which are coated on one or both faces (preferably both) with a suitable solvent-softened stiffening agent, such, for

example, as an ester of cellulose as at 4# This coating is preferably applied to the fabric before it is Adied out into stiffener blanks, and where two or more plies are employed, one at least of these plies is preferably somewhat larger than the others in order to form a marginal extension 5, particularlyvalong the rear edge ofthe toe stiifener to present a thin edge, thus eliminating the necessity of skiving the completed stifener to produce this desired thin edge which tends to avoid a visible'line of demarcation between the stiifened and unstifened portions of the completed shoe'. When the stiffeners are bein prepared, the blanks cut from vthe coate material are dipped into a suitable solvent for the particular stiening agent employed, and preferably. i

this is a non-aqueous volatile solvent which is so constituted that the time of setting of a stiffener softened by its use when the'stl'ener v is exposed to the air may be predetermined within reasonably close limits to conform to the requirements of the particular shoe facvao tory in which the shoes are to be made. A particularly suitable stiifening material is an ester of cellulose and the particular solvents which may be employed may vary considerably. Certain examples of such solvents are denatured alcohol, acetone, glycol ester derivatives such as diethylene, glycol monoethylether,x ethylene, glycolmonobutyl ether and ethyl acetate. The denatured alcohol and acetone are solvents which cause avery Short time of setting, while the glycol ester derivatives are slow in their action. The ethyl acetate is fast, but leaves an odor which in some cases may be objectionable. By properly combining these or other solvents, the time of setting of the stifening agent may be quite accurately predetermined from a few minutes to several hours.

Where more than one ply is used, both plies are dipped in the desired solvent and are then assembled in face to face relation, leaving the desired overlap about the margin, on a separator layer or sheet 6 to which the softened l stlifenlng agent will not stronglyadhere,

such, for example, as a sheet of waxed paper whlch 1s thin, non-absorbent and substantially unaffected lby the solvents. When a blank is dipped the'solvent is immediately absorbed by the fabric base and attacks the stifening agent, which, after it has been acted on for a suiicient length of time, is softened to a tacky condition. After a stiffener has been thus dlpped and laid on a separator sheet 6, another separator sheet is laid thereon and another stifl'ener is dipped and assembled on the second separator sheet, this process being carried on luntil a stack of alternate stiff'eners and separator sheets has been made to the desired number of stieners. 'The stack is then placed 1n a suitable container which may be hermetlcally sealed to avoid the evaporation vof solvent and to Apermit the stilfening'agent go soften and reach its desired tacky condilon.

When it is desired to use the stifeners the container is opened and the stifi'eners are pulled away one after another from their separator layers and placed in position in the shoes with the tacky face or faces against the desired shoe part or parts to whi ch the immediately adhere. ln order to facilitate the removal of' the individual stifeners from the separatorsheets and their assembly in the shoes without danger of injuring the tacky surface or soiling the fingers or shoe parts with the tacky material, each of the separator sheets may be provided with a portion such as 16, defined by weakened portions o r partial cuts as at 17 from the remainder of the sheet so that the shoe operative can fold one part of the weakened' portion over the edge of the stiflener, as .shown in Figure 4, thus to form with the remainder of the portion- 16 a non-sticky nger hold at the stifener edge. This may be grasped between the Laaace? ing operation, no difficulty is experienced by reason of the fact that this portion of the stiffener will not adhere to the shoe. Hence it is quite unnecessary to remove the portion 16 from the stiifener.

yThe external coating of stiening agent7 is acted on by the solvent while in contact with the separator layer and this layer has the effect to cause the surface coating when in softened condition to be of a 'jelly like consistency which condition adapts the stiifener admirably for immediate application to a shoe.

Certain embodiments of this invention having been thus described, it should be evident to those skilled in the art that various changes and modifications might be made therein without departing from the spirit or scope' of this invention as defined by the appended claims.

l claim:`

1. A shoe stiffener prepared for assembly in a shoe and comprising one or more fabric plies, and having an external face coating of a normally solid stifi'ening agent in a plastic tacky condition. v

2. A shoe stilfener prepared for assembly in a shoe and comprising one or more fabric plies, and having an external face coating of a normally solid solvent-softened stiifenlng agent pre-treated with the solvent and in a plastic tacky condition.

3. A shoe stiifener prepared for assembly in a. shoe and comprising one or more fabric plies, each ply having a surface coating of a normally solid stiffening agent in a plastic tacky condition, at least one of said coatings y being on one external face of the stifener.

4. A shoe stifener prepared for assembly in a shoe and comprising one or more fabric plies, each ply having a surface coating of a normally solid solvent-softened sti'ener agent pre-treated with the solvent and in a plastic tacky condition, at least one of said coatings beingl on one external face of the stiffener.

5. A shoe sti'ener prepared for assembly in a shoe and comprising one or more fabric plies, each ply having a surface coating of an ester of cellulose in a plastic tacky condition, at least one of said coatings being on one external face of the stiffener.

6. A shoe stiener prepared for assembly in a shoe and comprising one or more fabric plies coated on both faces with a normally solid stifl'ening agent in a plastic tacky condition.

7.. A shoe stiifener prepared for assembly in a shoe and comprismg one or more fabric plies coated on both faces with an ester of cellulose ina plastic tacky condition.

In testimony whereof I have yalixed my sgnature.

STANLEY P. LOV'ELL. 

